The performance of hydraulic and pneumatic components directly reflects the level of industry and automation. Hydraulic and pneumatic components are wearing parts, and their service life directly affects the advanced, stable and long-term nature of automation and industrial machinery. These are directly related to its processing accuracy, structural rationality, material properties, and processing methods. Sealing principle: According to its working principle, hydraulic and pneumatic seals are divided into squeeze seals and lip seals. Squeeze-type seals rely on the compressive deformation of the grooves to block the leak channel and obtain a sealing effect. The lip seal also relies on the pre-compressed elastic deformation of the filling groove to block the leakage channel. Under the pressure of the medium, the lip is further pressed against the counterpart to enhance the blocking and sealing effect.
Hydro-pneumatic fluid equipment
The hydraulic mechanism is a mechanism that uses hydraulic oil as a power source to complete predetermined motion requirements and implement various mechanism functions. Compared with pure mechanical mechanism and electric drive mechanism, the hydraulic mechanism has the following advantages:
(1) Under the condition of outputting the same power, the mechanism has a compact structure, small size, light weight and small inertia.
(2) The work is stable, the impact, vibration and noise are small, it is easy to realize frequent starting and reversing, and it can complete rotary motion and various reciprocating motions.
(3) Simple operation, convenient speed regulation, and stepless speed regulation can be realized in a large range, and the speed ratio can reach 5000.
(4) Low-speed and large-torque transmission is possible without the need for a reduction gear.
The disadvantages of the hydraulic mechanism are: the viscosity of the oil is greatly affected by temperature changes, and it is not suitable for use in low and high temperature environments; the processing and coordination of hydraulic components requires high precision, difficult processing technology and high cost.
The oil chamber in a positive displacement hydraulic pump is called an oil suction chamber when it is sucking oil. The pressure of the suction chamber is determined by the suction height and the resistance of the suction pipeline. If the suction height is too high or the resistance of the suction pipeline is too high, the vacuum of the suction chamber will be too high and it will affect the self-priming ability of the hydraulic pump. It is called the oil pressure chamber. The pressure of the oil pressure chamber depends on the external load and the pressure loss of the oil discharge pipe. In theory, the oil discharge pressure has nothing to do with the flow of the hydraulic pump.
The theoretical flow of displacement of a positive displacement hydraulic pump depends on the relevant geometry and speed of the hydraulic pump, and has nothing to do with the discharge pressure. However, the discharge pressure will affect the internal leakage of the pump and the amount of oil compression, thereby affecting the actual output flow of the pump, so the actual output flow of the hydraulic pump decreases with the increase of the discharge pressure.
Hydro-pneumatic fluid equipment